Study of the metastable helium spin polarization in an optically pumped afterglow

doi:10.1016/0168-9002(94)90080-9

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Volume 344, Issue 2, 1 May 1994, Pages 315-318

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Abstract

A very efficient technique of optical pumping is applied in order to polarize 2³S₁ metastable ⁴He atoms within an afterglow by means of a high power LNA laser. An almost complete atom polarization is achieved. This allows the production of an electron beam of appreciable intensity with high polarization well suited to perform a polarized electron source for linear cw accelerators.

References (10)

J. Arianer et al.
Nucl. Instr. and Meth. A
(1993)
Chu Cheng et al.
Rev. Sci. Instr.
(1982)
M.V. McCuster et al.
Phys. Rev. A
(1972)
F.D. Colegrove et al.
Phys. Rev.
(1960)
G.H. Rutherford et al.
Rev. Sci. Instr.
(1990)

There are more references available in the full text version of this article.

Cited by (4)

Characterization of the SELPO-M polarized electron source on a 100 kV platform
1999, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
A source of polarized electrons based on a helium flowing afterglow has been developed at Orsay. This source, SELPO-M, has been placed on a 100 kV platform and set up in such a way as to allow its connection to the MAMI accelerator. Its performances in terms of current, polarization and optical properties are given. Its figure of merit (IP²≃75 μA) appears highly competitive as compared to strained GaAs sources.
A flowing afterglow as a polarized electron source
1996, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
A source of polarized electrons based on a helium flowing afterglow has been developed at Orsay. The different parts of the device are described. The results about the polarization of the metastable He atoms, the electron current and polarization and optical properties of the output electron beam are given. They reveal electron polarizations in the range 70–82% for currents up to 30 μA, about 60% for 100 μA, an average emittance of 0.5π mm mrad and an energy spread of 0.25 eV.
Metastable-metastable collisions in the Orsay polarized electron source by helium afterglow
1995, Nuclear Inst. and Methods in Physics Research, A
At Orsay the current of polarized electrons produced by the optically pumped helium afterglow does not vary as the metastable density, but as the density squared. That shows that spurious electrons are mixed to the electrons emitted by chemi-ionization reaction of the polarized metastables with CO₂ gas. In this paper it is suggested that these spurious electrons are produced by metastable-metastable collisions. The contribution of these collisions to the electron current and polarization is evaluated.
Use of a diode laser to measure the polarization of an optically pumped ensemble of He(2 <sup>3</sup>S) atoms
1996, Review of Scientific Instruments

^∗: Corresponding author.

¹: Permanent address: Physics Department, University of Missouri Rolla, MO 65401.

^†: Died on the 7th of March 1993.

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Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Study of the metastable helium spin polarization in an optically pumped afterglow

Abstract

Nucl. Instr. and Meth. A

Rev. Sci. Instr.

Phys. Rev. A

Phys. Rev.

Rev. Sci. Instr.

Characterization of the SELPO-M polarized electron source on a 100 kV platform

A flowing afterglow as a polarized electron source

Metastable-metastable collisions in the Orsay polarized electron source by helium afterglow

Use of a diode laser to measure the polarization of an optically pumped ensemble of He(2 <sup>3</sup>S) atoms